The present invention relates to a print control method in which code data such as PDL is converted into image data and printing is carried out.
Conventionally, when printing a document prepared by a personal computer (PC) or the like, a document prepared by an application program with use of a driver or library of the PC is converted into code data called a page description language (PDL) such as postscript or PCL. The code data is transferred to a printer through a network to perform printing. The printer comprises a printer controller and a printer engine. The printer controller interprets the code data to prepare a document image of a bit map. The printer engine receives the image data through a video I/F from the printer controller and performs printing onto a paper sheet. If the printer has a library for developing a file of an application program into an image, it is considered that printing can be achieved from an application file (in form of code data).
In recent years, networks have been developed and environments for network printers as described above have been almost prepared. However, it takes a long time to develop code data such as PDL into a bit map image, and besides, a sorting device or a finisher has not yet been sufficiently prepared. Therefore, a first set of a document is printed by a network printer and copies are prepared by a copying machine where a plurality of sets of copies are required.
In order to print a plurality of sets of a document, rendering processing for developing every page into an image is carried out, and image data after rendering is stored into a hard disk (HDD) directly or after compression. When printing a second or later set of the document, image data stored in the HDD or compressed data is expanded to perform a printing output without performing rendering. Since rendering is processing which takes a very long time, image data once prepared by rendering is thus stored into a HDD and is used for printing a plurality of sets of a document. The time required for rendering can be abbreviated and the processing speed can be improved. However, when the storage capacity of the HDD is full, image data itself cannot be stored and rendering must be carried out based on code data as for second and later sets of a document, resulting in a problem that printing cannot be performed at a higher speed.
As has been explained above, a conventional printer controller has a problem that no idea has not been made to improve the printing speed in consideration of the rendering time and the data amount of image data prepared by rendering.
The present invention has an object of providing a print control method capable of printing a plurality of sets of one same document by efficiently storing image data after rendering in consideration of a rendering time and a data amount of image data prepared by rendering, and a printing apparatus using the print control method.
The present invention provides an image forming apparatus comprises preparing means for preparing print data for every page corresponding to inputted code data; storage means for storing the print data prepared by the preparing means; printing means for performing printing corresponding to the print data stored by the storage means when there is any print data stored by the storage means, and corresponding to the print data prepared by the preparing means when no print data is stored by the storage means; and controlling means for comparing a data amount of the print data with an empty capacity of the storage means, and for controlling the storage means so as to store the print data when the empty capacity is larger than the data amount, and for controlling the storage means so as not to store the print data and controlling each means such that the data amount is not compared with the empty capacity when the data amount is smaller than the empty amount.
As described above, the present invention provides an image forming apparatus in which print data subjected to rendering is stored into an empty area if an empty area exists in a storage area. For example, in case where a printer is connected to a personal computer and a plurality of sets each consisting of a document of a plurality of pages and the plurality of sets each consisting of a plurality of pages are to be printed in the structure as described above, image data subjected to rendering in printing of a first set of the document is not erased but is stored into a hard disk or the like. In this manner, the image data can be used for printing a second or later set of the document. In this arrangement, rendering processing which requires a long processing time can be omitted from the operation for printing the second and later sets of the document, so that the entire print processing time can be shortened. Further, it should be noted that image data is not stored evenly but image data is stored as much as possible. When it is determined that image data cannot be stored any more, any more image data is not stored. As for the second and later sets of the document, image data which can be used and which has been stored is used, and those pages whose image data has not been stored are subjected to rendering processing for every page.
According to another embodiment of the present invention, the determination as to whether or not image data should be stored is made in various ways. In association with fine storage processing and data deletion processing matched with the situation, rendering processing and storage processing of image data can be performed under an optimal condition. As a result, the present invention does not use evenly image data but performs optimal processing, depending upon circumstances, unlike a conventional apparatus. It is therefore possible to provide an image forming apparatus which realizes rapid print processing with the highest efficiency, and an image processing method using the apparatus.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.